Deals from Pfizer, Novartis and AstraZeneca. Also: Snake Oil.

Novartis is buying closely held Corthera for $120 million. That gives the company the rights to a drug called Relaxin, which is in late-stage trials for acute heart failure. Current Corthera shareholders could get hundreds of millions more in milestone payments if the drug pans out (always an iffy proposition).

Novartis is also likely to expand its stake in Alcon soon, WSJ’s Deal Journal said yesterday. The company already has purchased a quarter of the company from Nestlé and is likely to buy another 52%, maybe more. Alcon sells eye-care products, and the buy is a diversification play.

AstraZeneca will pay $350 million to buy Novexel, a company that specializes in new antibiotics, plus another $80 million for the company’s cash. Forest Labs is also in on the deal — the company will pay AstraZeneca half of what it spent on the Novexel deal, and will share development costs of Novexel’s lead experimental compounds. The medicines aim to treat infections that are resistant to existing antibiotics. For all of the wrinkles in the deal, see this story from Dow Jones Newswires.

Pfizer is licensing an experimental drug out to Medicines Co., a small drug maker. Despite the deal’s size, (the upfront payment is only $10 million), it’s a good reminder that deals can flow both ways: Besides prowling for drugs to bring in from smaller players, giants like Pfizer also have drugs in their pipeline they’re looking to license out for a price. In this case, the drug is a cholesterol medicine called ApoA-I Milano, described in this clinical trial published in JAMA in 2003.

Amgen and Roche ended a long fight over anemia drugs. Roche admitted that certain Amgen patents are valid, enforceable and infringed on by Roche’s anemia drug Mircera, Reuters reports. That means Amgen’s drug Aranesp isn’t likely to face generic competition in the U.S. until 2014. A court had already issued an injunction keeping Mircera off the market here.

Earlier filings in the case were pretty spirited. “With all the sincerity of a snake-oil salesman, Roche hyped its infringing product as a purportedly ‘new’ medicine conferring a different medical benefit,” Amgen’s lawyers wrote. Roche said it had acted fairly.